Eclipse學習之三：Eclipse開發Struts應用

在配置好Structs開發環境的基礎上

 

1  配置Struts的映射地址

2  配置<form-bean>: 添加登錄表單loginForm

3  配置<action>：添加登錄組件login

4  開發ActionForm Bean：創建登錄表單類LoginForm.java

5  開發Action：創建登錄處理類LoginAction.java

 

1  在使用Struts進行開發時 需要避免對JSP文件的直接訪問 這樣做的目的是爲了將所有的請求都交給Struts來統一處理

在web.xml中進行映射配置

<servlet-mapping>
        <servlet-name>action</servlet-name>
        <url-pattern>*.do</url-pattern>
    </servlet-mapping>

對於每一個name.do的請求 都必須在struts-config.xml中配置與"name"對應的組件 該組件是通過<action>元素來註冊的 使用<action>的第一種配置形式-直接轉發方式 來配置一個地址"index.do" 負責轉發到登錄頁面login.jsp

<action path="/index" forward="/login.jsp"
/>

 

2  修改login.jsp的登錄提交地址爲login.do

<form
name="form1"
action="login.do"
method="post">

3  配置<form-bean> : 添加登錄表單loginForm

<form-bean name="loginForm"
            type="com.demo.struts.forms.LoginForm">
        </form-bean>

4  配置<action>：添加登錄組件login

<action path="/login" name="loginForm"
scope="request"
            type="com.demo.struts.actions.LoginAction" input="/login.jsp">
            <forward name="success" path="/welcome.jsp"
/>
            <forward name="failure" path="/login.jsp"
/>
        </action>

5  開發ActionForm Bean：創建登錄表單類 LoginForm.java

 

package com.demo.struts.forms;

public 
class LoginForm extends ActionForm 
{

    proteced String username = nill;

     protected String password = null;

    public String getPassword() {

        return password;
    }

    public 
void setPassword(String password)
{
        this.password
= password;
    }

    public 
String getUsername()
{
        return username;
    }

    public 
void setUsername(String username)
{
        this.username
= username;
    }
}

6  開發Action 創建登錄處理類LoginAction.java

 

package com.demo.struts.actions;

import 
java.sql.Connection;
import 
java.sql.ResultSet;
import 
java.sql.Statement;

import 
javax.servlet.http.HttpServletRequest;
import 
javax.servlet.http.HttpServletResponse;
import 
javax.servlet.http.HttpSession;
import 
javax.sql.DataSource;

import 
org.apache.log4j.Logger;
import 
org.apache.struts.action.ActionErrors;
import 
org.apache.struts.action.ActionForm;
import 
org.apache.struts.action.ActionForward;
import 
org.apache.struts.action.ActionMapping;
import 
org.apache.struts.action.ActionMessage;
import 
org.apache.struts.actions.DispatchAction;

public 
class LoginAction extends DispatchAction
{


    public ActionForward
execute(ActionMapping mapping, ActionForm form,
            HttpServletRequest 
request, HttpServletResponse response)
            throws
Exception {

        ActionErrors errors 
= new ActionErrors();
        ActionForward forward 
= new ActionForward();
        LoginForm loginForm 
= (LoginForm) form;

        try 
{
            // get parameters
            String username
= loginForm.getUsername();
            String password
= loginForm.getPassword();
            // invalidate the original session if exists

            HttpSession session 
= request.getSession(false);
            if
(session !=
null) 
{
                session.invalidate();
            }

            // create a new session for the user

            session 
= request.getSession(true);

            // login

            boolean
isValid = 
false;
            if (username.equals("admin")&&password.equals("admin"))
            {
               isValid = true;
             }
            if
(isValid)
{
                session.setAttribute(Constants.USERNAME_KEY,
username);

            }
else {
                errors.add(ActionErrors.GLOBAL_MESSAGE,
new ActionMessage(
                        "login.message.failed"));
            }

        } 
catch (Exception e)
{
            errors.add(ActionErrors.GLOBAL_MESSAGE,
new ActionMessage(
                    "login.message.failed"));

        }

        // If a message is required, save the specified key(s)

        // into the request for use by the <struts:errors> tag.


        if 
(!errors.isEmpty())
{
            saveErrors(request, errors);

            forward 
= mapping.findForward(Constants.FAILURE_KEY);
        } 
else {
            forward 
= mapping.findForward(Constants.SUCCESS_KEY);
        }

        // Finish with

        return
(forward);
    }

}